Application of MSCT characteristic nomogram model in predicting invasion of pancreatic solid pseudopapillary neoplasms

•This study explored MSCT features in predicting tumor invasion of pancreatic solid pseudopapillary neoplasms (pSPN), a subset has rarely been investigated individually.•The independent predictors of pSPN invasion included growth pattern, annular enhancement, capsule, and CT value of lesion in arterial phase.•A nomogram for individualized risk estimation of tumor invasion provides great diagnostic confidence. To evaluate the value of multi-slice computed tomography (MSCT) characteristic nomogram model in predicting invasion of pancreatic solid pseudopapillary neoplasms (pSPN). From January 2016 to January 2021, the clinical characteristics, pathology and imaging data of 114 patients with pSPN were retrospectively analyzed. 42 cases were classified in invasive group while 72 cases in non-invasive group. The tumor location, shape, growth pattern, growth angle, margin calcification, floating cloud sign, annular enhancement, pancreatic and bile duct dilation, distal pancreatic atrophy, capsule, cystic degeneration and cystic to solid ratio between the two groups were analyzed. The maximum diameter and the CT value of the solid parts in the lesion were measured. There were significant differences in tumor shape, growth pattern, margin, annular enhancement, capsule, CT value in arterial phase and venous phase (P 0.05). The independent predictors of pSPN invasion included growth pattern, annular enhancement, capsule, and CT value of lesion in arterial phase. A nomogram model was successfully established to predict the invasion of pSPN. The area under the receiver operating characteristic curve was 0.888, and the calibration prediction curve was in good agreement with the standard curve. The nomogram model based on MSCT features has high application value in preoperative prediction of tumor invasion of pancreatic solid pseudopapillary neoplasms.